From 4e75b2fb8381584f29c5a05094c5220c2b108c71 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20Vondru=C5=A1?= <mosra@centrum.cz>
Date: Sat, 23 May 2015 13:28:11 +0200
Subject: [PATCH] First-class WebGL support, part 8: reduced query
 functionality.

---
 src/Magnum/AbstractQuery.cpp           | 24 ++++++------------
 src/Magnum/AbstractQuery.h             | 11 ++++++--
 src/Magnum/CMakeLists.txt              | 35 ++++++++++++++++----------
 src/Magnum/Implementation/QueryState.h |  4 +++
 src/Magnum/Implementation/State.cpp    |  4 +++
 src/Magnum/Implementation/State.h      |  4 +++
 src/Magnum/PrimitiveQuery.h            | 10 ++++----
 src/Magnum/Query.h                     |  4 +++
 src/Magnum/SampleQuery.h               | 23 ++++++++++++-----
 src/Magnum/TimeQuery.h                 |  9 ++++++-
 10 files changed, 85 insertions(+), 43 deletions(-)

diff --git a/src/Magnum/AbstractQuery.cpp b/src/Magnum/AbstractQuery.cpp
index 3e224a5b8..0ce9fb1d6 100644
--- a/src/Magnum/AbstractQuery.cpp
+++ b/src/Magnum/AbstractQuery.cpp
@@ -98,10 +98,8 @@ bool AbstractQuery::resultAvailable() {
     GLuint result;
     #ifndef MAGNUM_TARGET_GLES2
     glGetQueryObjectuiv(_id, GL_QUERY_RESULT_AVAILABLE, &result);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN)
-    glGetQueryObjectuivEXT(_id, GL_QUERY_RESULT_AVAILABLE_EXT, &result);
     #else
-    CORRADE_ASSERT_UNREACHABLE();
+    glGetQueryObjectuivEXT(_id, GL_QUERY_RESULT_AVAILABLE_EXT, &result);
     #endif
     return result == GL_TRUE;
 }
@@ -111,21 +109,20 @@ template<> UnsignedInt AbstractQuery::result<UnsignedInt>() {
     UnsignedInt result;
     #ifndef MAGNUM_TARGET_GLES2
     glGetQueryObjectuiv(_id, GL_QUERY_RESULT, &result);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN)
-    glGetQueryObjectuivEXT(_id, GL_QUERY_RESULT_EXT, &result);
     #else
-    CORRADE_ASSERT_UNREACHABLE();
+    glGetQueryObjectuivEXT(_id, GL_QUERY_RESULT_EXT, &result);
     #endif
     return result;
 }
 
 template<> bool AbstractQuery::result<bool>() { return result<UnsignedInt>() != 0; }
 
+#ifndef MAGNUM_TARGET_WEBGL
 template<> Int AbstractQuery::result<Int>() {
     Int result;
     #ifndef MAGNUM_TARGET_GLES
     glGetQueryObjectiv(_id, GL_QUERY_RESULT, &result);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #elif !defined(CORRADE_TARGET_NACL)
     glGetQueryObjectivEXT(_id, GL_QUERY_RESULT_EXT, &result);
     #else
     CORRADE_ASSERT_UNREACHABLE();
@@ -133,12 +130,11 @@ template<> Int AbstractQuery::result<Int>() {
     return result;
 }
 
-#ifndef MAGNUM_TARGET_WEBGL
 template<> UnsignedLong AbstractQuery::result<UnsignedLong>() {
     UnsignedLong result;
     #ifndef MAGNUM_TARGET_GLES
     glGetQueryObjectui64v(_id, GL_QUERY_RESULT, &result);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #elif !defined(CORRADE_TARGET_NACL)
     glGetQueryObjectui64vEXT(_id, GL_QUERY_RESULT_EXT, &result);
     #else
     CORRADE_ASSERT_UNREACHABLE();
@@ -150,7 +146,7 @@ template<> Long AbstractQuery::result<Long>() {
     Long result;
     #ifndef MAGNUM_TARGET_GLES
     glGetQueryObjecti64v(_id, GL_QUERY_RESULT, &result);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN) && !defined(CORRADE_TARGET_NACL)
+    #elif !defined(CORRADE_TARGET_NACL)
     glGetQueryObjecti64vEXT(_id, GL_QUERY_RESULT_EXT, &result);
     #else
     CORRADE_ASSERT_UNREACHABLE();
@@ -167,10 +163,8 @@ void AbstractQuery::begin() {
 
     #ifndef MAGNUM_TARGET_GLES2
     glBeginQuery(_target, _id);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN)
-    glBeginQueryEXT(_target, _id);
     #else
-    CORRADE_ASSERT_UNREACHABLE();
+    glBeginQueryEXT(_target, _id);
     #endif
 }
 
@@ -190,10 +184,8 @@ void AbstractQuery::end() {
 
     #ifndef MAGNUM_TARGET_GLES2
     glEndQuery(_target);
-    #elif !defined(CORRADE_TARGET_EMSCRIPTEN)
-    glEndQueryEXT(_target);
     #else
-    CORRADE_ASSERT_UNREACHABLE();
+    glEndQueryEXT(_target);
     #endif
 }
 
diff --git a/src/Magnum/AbstractQuery.h b/src/Magnum/AbstractQuery.h
index fa851f2d7..5f0c0730a 100644
--- a/src/Magnum/AbstractQuery.h
+++ b/src/Magnum/AbstractQuery.h
@@ -25,9 +25,11 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 /** @file
  * @brief Class @ref Magnum::AbstractQuery
  */
+#endif
 
 #include <Corrade/Containers/Array.h>
 #include <Corrade/Utility/Assert.h>
@@ -35,6 +37,7 @@
 #include "Magnum/AbstractObject.h"
 #include "Magnum/configure.h"
 
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 namespace Magnum {
 
 namespace Implementation { struct QueryState; }
@@ -44,6 +47,7 @@ namespace Implementation { struct QueryState; }
 
 See @ref PrimitiveQuery, @ref SampleQuery and @ref TimeQuery documentation for
 more information.
+@requires_webgl20 Queries are not available in WebGL 1.0.
 @todo `QUERY_COUNTER_BITS` (not sure since when this is supported)
 */
 class MAGNUM_EXPORT AbstractQuery: public AbstractObject {
@@ -116,8 +120,6 @@ class MAGNUM_EXPORT AbstractQuery: public AbstractObject {
          *
          * Note that this function is blocking until the result is available.
          * See @ref resultAvailable().
-         * @attention @ref Magnum::UnsignedLong "UnsignedLong" and @ref Magnum::Long "Long"
-         *      result type is not available in @ref MAGNUM_TARGET_WEBGL "WebGL".
          * @see @fn_gl{GetQueryObject} with @def_gl{QUERY_RESULT}
          * @requires_gl33 Extension @extension{ARB,timer_query} for result
          *      type @ref Magnum::UnsignedInt "UnsignedInt" and @ref Magnum::Long
@@ -125,6 +127,8 @@ class MAGNUM_EXPORT AbstractQuery: public AbstractObject {
          * @requires_es_extension Extension @es_extension{EXT,disjoint_timer_query}
          *      for result types @ref Magnum::Int "Int", @ref Magnum::UnsignedLong "UnsignedLong"
          *      @ref Magnum::Long "Long".
+         * @requires_gles Only @ref Magnum::UnsignedInt "UnsignedInt" result
+         *      type is available in WebGL.
          */
         template<class T> T result();
 
@@ -199,5 +203,8 @@ inline AbstractQuery& AbstractQuery::operator=(AbstractQuery&& other) noexcept {
 }
 
 }
+#else
+#error this header is not available in WebGL 1.0 build
+#endif
 
 #endif
diff --git a/src/Magnum/CMakeLists.txt b/src/Magnum/CMakeLists.txt
index 35bcb09a9..0a90005a6 100644
--- a/src/Magnum/CMakeLists.txt
+++ b/src/Magnum/CMakeLists.txt
@@ -31,7 +31,6 @@ set(Magnum_SRCS
     AbstractFramebuffer.cpp
     AbstractImage.cpp
     AbstractObject.cpp
-    AbstractQuery.cpp
     AbstractTexture.cpp
     AbstractShaderProgram.cpp
     Attribute.cpp
@@ -57,7 +56,6 @@ set(Magnum_SRCS
     Implementation/BufferState.cpp
     Implementation/FramebufferState.cpp
     Implementation/MeshState.cpp
-    Implementation/QueryState.cpp
     Implementation/RendererState.cpp
     Implementation/ShaderProgramState.cpp
     Implementation/State.cpp
@@ -83,7 +81,6 @@ set(Magnum_HEADERS
     AbstractFramebuffer.h
     AbstractImage.h
     AbstractObject.h
-    AbstractQuery.h
     AbstractResourceLoader.h
     AbstractShaderProgram.h
     AbstractTexture.h
@@ -110,13 +107,11 @@ set(Magnum_HEADERS
     Resource.h
     ResourceManager.h
     ResourceManager.hpp
-    SampleQuery.h
     Sampler.h
     Shader.h
     Texture.h
     TextureFormat.h
     Timeline.h
-    TimeQuery.h
     Types.h
     Version.h
 
@@ -128,19 +123,12 @@ set(Magnum_PRIVATE_HEADERS
     Implementation/FramebufferState.h
     Implementation/maxTextureSize.h
     Implementation/MeshState.h
-    Implementation/QueryState.h
     Implementation/RendererState.h
     Implementation/ShaderProgramState.h
     Implementation/ShaderState.h
     Implementation/State.h
     Implementation/TextureState.h)
 
-# Deprecated headers
-if(BUILD_DEPRECATED)
-    set(Magnum_HEADERS ${Magnum_HEADERS}
-        Query.h)
-endif()
-
 # Desktop-only stuff
 if(NOT TARGET_GLES)
     list(APPEND Magnum_SRCS
@@ -182,7 +170,8 @@ if(NOT TARGET_WEBGL)
         Implementation/DebugState.cpp)
 
     list(APPEND Magnum_HEADERS
-        DebugOutput.h)
+        DebugOutput.h
+        TimeQuery.h)
 
     list(APPEND Magnum_PRIVATE_HEADERS
         Implementation/DebugState.h)
@@ -199,6 +188,26 @@ if(NOT TARGET_WEBGL)
     endif()
 endif()
 
+# Desktop, OpenGL ES and WebGL 2.0 stuff that is not available in WebGL 1.0
+if(NOT (TARGET_WEBGL AND TARGET_GLES2))
+    list(APPEND Magnum_SRCS
+        AbstractQuery.cpp
+
+        Implementation/QueryState.cpp)
+
+    list(APPEND Magnum_HEADERS
+        AbstractQuery.h
+        SampleQuery.h)
+
+    list(APPEND Magnum_PRIVATE_HEADERS
+        Implementation/QueryState.h)
+
+    if(BUILD_DEPRECATED)
+        list(APPEND Magnum_HEADERS
+            Query.h)
+    endif()
+endif()
+
 # Link in GL function pointer variables on platforms that support it
 if(NOT CORRADE_TARGET_EMSCRIPTEN AND NOT CORRADE_TARGET_NACL)
     list(APPEND Magnum_SRCS $<TARGET_OBJECTS:MagnumFlextGLObjects>)
diff --git a/src/Magnum/Implementation/QueryState.h b/src/Magnum/Implementation/QueryState.h
index e05a3d45d..363ec5b8f 100644
--- a/src/Magnum/Implementation/QueryState.h
+++ b/src/Magnum/Implementation/QueryState.h
@@ -29,6 +29,10 @@
 
 #include "Magnum/AbstractQuery.h"
 
+#if defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2)
+#error this header is not available in WebGL 1.0 build
+#endif
+
 namespace Magnum { namespace Implementation {
 
 struct QueryState {
diff --git a/src/Magnum/Implementation/State.cpp b/src/Magnum/Implementation/State.cpp
index 7f2b8ca8a..5779529f1 100644
--- a/src/Magnum/Implementation/State.cpp
+++ b/src/Magnum/Implementation/State.cpp
@@ -36,7 +36,9 @@
 #endif
 #include "FramebufferState.h"
 #include "MeshState.h"
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 #include "QueryState.h"
+#endif
 #include "RendererState.h"
 #include "ShaderState.h"
 #include "ShaderProgramState.h"
@@ -63,7 +65,9 @@ State::State(Context& context) {
     #endif
     framebuffer.reset(new FramebufferState{context, extensions});
     mesh.reset(new MeshState{context, extensions});
+    #if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
     query.reset(new QueryState{context, extensions});
+    #endif
     renderer.reset(new RendererState{context, extensions});
     shader.reset(new ShaderState);
     shaderProgram.reset(new ShaderProgramState{context, extensions});
diff --git a/src/Magnum/Implementation/State.h b/src/Magnum/Implementation/State.h
index 8519f8a73..76a786478 100644
--- a/src/Magnum/Implementation/State.h
+++ b/src/Magnum/Implementation/State.h
@@ -38,7 +38,9 @@ struct DebugState;
 #endif
 struct FramebufferState;
 struct MeshState;
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 struct QueryState;
+#endif
 struct RendererState;
 struct ShaderState;
 struct ShaderProgramState;
@@ -61,7 +63,9 @@ struct State {
     #endif
     std::unique_ptr<FramebufferState> framebuffer;
     std::unique_ptr<MeshState> mesh;
+    #if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
     std::unique_ptr<QueryState> query;
+    #endif
     std::unique_ptr<RendererState> renderer;
     std::unique_ptr<ShaderState> shader;
     std::unique_ptr<ShaderProgramState> shaderProgram;
diff --git a/src/Magnum/PrimitiveQuery.h b/src/Magnum/PrimitiveQuery.h
index 398ff59c4..eb3fdf40d 100644
--- a/src/Magnum/PrimitiveQuery.h
+++ b/src/Magnum/PrimitiveQuery.h
@@ -59,10 +59,10 @@ if(!q.resultAvailable()) {
 // ...or block until the result is available
 UnsignedInt primitiveCount = q.result<UnsignedInt>();
 @endcode
-@requires_gl30 Extension @extension{EXT,transform_feedback}
-@requires_gles30 Only sample queries are available on OpenGL ES 2.0.
-
 @see @ref SampleQuery, @ref TimeQuery, @ref TransformFeedback
+@requires_gl30 Extension @extension{EXT,transform_feedback}
+@requires_gles30 Only sample queries are available in OpenGL ES 2.0.
+@requires_webgl20 Queries are not available in WebGL 1.0.
 @todo glBeginQueryIndexed
 @todo @extension{ARB,transform_feedback_overflow_query}
 */
@@ -75,7 +75,7 @@ class PrimitiveQuery: public AbstractQuery {
              * Count of primitives generated from vertex shader or geometry
              * shader.
              * @requires_gl Only transform feedback query is available in
-             *      OpenGL ES.
+             *      OpenGL ES and WebGL.
              */
             PrimitivesGenerated = GL_PRIMITIVES_GENERATED,
             #endif
@@ -96,7 +96,7 @@ class PrimitiveQuery: public AbstractQuery {
          * @brief Constructor
          *
          * Creates new OpenGL query object. If @extension{ARB,direct_state_access}
-         * (part of OpenGL 4.5) is not supported, the query is created on first
+         * (part of OpenGL 4.5) is not available, the query is created on first
          * use.
          * @see @fn_gl{CreateQueries}, eventually @fn_gl{GenQueries}
          */
diff --git a/src/Magnum/Query.h b/src/Magnum/Query.h
index 452a03f09..9a1ae0b3f 100644
--- a/src/Magnum/Query.h
+++ b/src/Magnum/Query.h
@@ -32,6 +32,7 @@
 
 #include "Magnum/configure.h"
 
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 #ifdef MAGNUM_BUILD_DEPRECATED
 #include "Magnum/PrimitiveQuery.h"
 #include "Magnum/SampleQuery.h"
@@ -39,5 +40,8 @@
 #else
 #error use Magnum/PrimitiveQuery.h, Magnum/SampleQuery.h or Magnum/TimeQuery.h instead.
 #endif
+#else
+#error this header is not available in WebGL 1.0 build
+#endif
 
 #endif
diff --git a/src/Magnum/SampleQuery.h b/src/Magnum/SampleQuery.h
index 74f8c7d43..2fe71d2bc 100644
--- a/src/Magnum/SampleQuery.h
+++ b/src/Magnum/SampleQuery.h
@@ -25,9 +25,11 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 /** @file
  * @brief Class @ref Magnum::SampleQuery
  */
+#endif
 
 #include "Magnum/AbstractQuery.h"
 
@@ -35,6 +37,7 @@
 #include <Corrade/Utility/Macros.h>
 #endif
 
+#if !(defined(MAGNUM_TARGET_WEBGL) && defined(MAGNUM_TARGET_GLES2))
 namespace Magnum {
 
 /**
@@ -74,7 +77,8 @@ q.endConditionalRender();
 
 @see @ref PrimitiveQuery, @ref TimeQuery
 @requires_gles30 Extension @es_extension{EXT,occlusion_query_boolean} in
-    OpenGL ES 2.0
+    OpenGL ES 2.0.
+@requires_webgl20 Queries are not available in WebGL 1.0.
 */
 class SampleQuery: public AbstractQuery {
     public:
@@ -83,7 +87,8 @@ class SampleQuery: public AbstractQuery {
             #ifndef MAGNUM_TARGET_GLES
             /**
              * Count of samples passed from fragment shader
-             * @requires_gl Only boolean query is available in OpenGL ES.
+             * @requires_gl Only boolean query is available in OpenGL ES and
+             *      WebGL.
              */
             SamplesPassed = GL_SAMPLES_PASSED,
             #endif
@@ -117,7 +122,8 @@ class SampleQuery: public AbstractQuery {
          * @brief Conditional render mode
          *
          * @requires_gl30 Extension @extension{NV,conditional_render}
-         * @requires_gl Conditional rendering is not available in OpenGL ES.
+         * @requires_gl Conditional rendering is not available in OpenGL ES or
+         *      WebGL.
          */
         enum class ConditionalRenderMode: GLenum {
             /**
@@ -189,7 +195,7 @@ class SampleQuery: public AbstractQuery {
          * @brief Constructor
          *
          * Creates new OpenGL query object. If @extension{ARB,direct_state_access}
-         * (part of OpenGL 4.5) is not supported, the query is created on first
+         * (part of OpenGL 4.5) is not available, the query is created on first
          * use.
          * @see @fn_gl{CreateQueries}, eventually @fn_gl{GenQueries}
          */
@@ -213,7 +219,8 @@ class SampleQuery: public AbstractQuery {
          *
          * @see @fn_gl{BeginConditionalRender}
          * @requires_gl30 Extension @extension{NV,conditional_render}
-         * @requires_gl Conditional rendering is not available in OpenGL ES.
+         * @requires_gl Conditional rendering is not available in OpenGL ES or
+         *      WebGL.
          */
         void beginConditionalRender(ConditionalRenderMode mode) {
             glBeginConditionalRender(id(), GLenum(mode));
@@ -224,7 +231,8 @@ class SampleQuery: public AbstractQuery {
          *
          * @see @fn_gl{EndConditionalRender}
          * @requires_gl30 Extension @extension{NV,conditional_render}
-         * @requires_gl Conditional rendering is not available in OpenGL ES.
+         * @requires_gl Conditional rendering is not available in OpenGL ES or
+         *      WebGL.
          */
         void endConditionalRender() {
             glEndConditionalRender();
@@ -245,5 +253,8 @@ class SampleQuery: public AbstractQuery {
 };
 
 }
+#else
+#error this header is not available in WebGL 1.0 build
+#endif
 
 #endif
diff --git a/src/Magnum/TimeQuery.h b/src/Magnum/TimeQuery.h
index 662f5e541..1315ea14c 100644
--- a/src/Magnum/TimeQuery.h
+++ b/src/Magnum/TimeQuery.h
@@ -25,9 +25,11 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#ifndef MAGNUM_TARGET_WEBGL
 /** @file
  * @brief Class @ref Magnum::TimeQuery
  */
+#endif
 
 #include "Magnum/AbstractQuery.h"
 
@@ -35,6 +37,7 @@
 #include <Corrade/Utility/Macros.h>
 #endif
 
+#ifndef MAGNUM_TARGET_WEBGL
 namespace Magnum {
 
 /**
@@ -68,6 +71,7 @@ UnsignedInt timeElapsed2 = q3.result<UnsignedInt>()-tmp;
 Using the latter results in fewer OpenGL calls when doing more measures.
 @requires_gl33 Extension @extension{ARB,timer_query}
 @requires_es_extension Extension @es_extension{EXT,disjoint_timer_query}
+@requires_gles Time query is not available in WebGL.
 
 @see @ref PrimitiveQuery, @ref SampleQuery
 @todo timestamp with glGet + example usage
@@ -104,7 +108,7 @@ class TimeQuery: public AbstractQuery {
          * @brief Constructor
          *
          * Creates new OpenGL query object. If @extension{ARB,direct_state_access}
-         * (part of OpenGL 4.5) is not supported, the query is created on first
+         * (part of OpenGL 4.5) is not available, the query is created on first
          * use.
          * @see @fn_gl{CreateQueries}, eventually @fn_gl{GenQueries}
          */
@@ -151,5 +155,8 @@ class TimeQuery: public AbstractQuery {
 };
 
 }
+#else
+#error this header is not available in WebGL 1.0 build
+#endif
 
 #endif